The subject invention relates to improved multilayered products and methods for manufacturing such products. More particularly, the subject invention relates to improved semiconductor products such as thin film read/write heads and methods for manufacturing such heads.
Underlayers play an important role in the formation of appropriate crystallographic textures of overlaid films in many applications. Typically, an underlayer is chosen such that the plane of atoms at the interface between layers provides an appropriate template to encourage growth of the overlaid film in a desired texture. Thus, the underlayer itself has to be grown in the correct texture and must have the correct lattice dimensions to promote this epitaxy.
Examples of a multilayer system contemplated here are the Cr/CoCrPt systems used in making thin film permanent magnets and Cr/Ta systems used for making electrical lead material. These permanent magnets and leads are important elements of thin film magnetic recording heads which are used in data storage devices like computer hard drives. A typical permanent magnet for such application may have a Cr underlayer having a thickness of about 20 angstroms to about 100 angstroms and a CoCrPt overlayer having a thickness of about 100 angstroms to about 1000 angstroms.
As requirements for greater storage density increase, there is a great need to be able to make ultra sensitive heads which, while having enhanced properties, can be made reliably with reasonable manufacturing expense.